Pyro

Pyros are the up close and personal class. They're terrible in ranged confrontations, so they like to choose their battles wisely and lay traps. Though classified by Valve as attackers, they also make solid defenders in tight corridors.

• Ambush! It's what Pyros do best. If the enemy spots you, let them come to you. Your flamethrower is only effective at close range, so you don't want to try and engage the enemy at a distance.

• Get close while you attack. It can disorient the enemy and will make your flamethrower do more damage. The only thing they'll see is a shower of flames before it's all over.

Defense

Demoman

Valve says these guys are defenders, and though their sticky grenades make them excellent at setting traps, their standard grenade launcher also makes them one of the best attackers. A Demoman is right at home charging behind a Heavy Weapons Guy and firing grenades over his head to clear the path.

• The grenade launcher is great for flushing out snipers and soldiers that are above you. Run up underneath their ledge and then let them have it. They'll usually be focused off in the distance behind you and not even see you coming.

• The Demoman is the only class with indirect fire, meaning you don't need line of sight on an enemy to do damage to them. Bounce your grenades around corners to destroy turrets and advancing enemies.

• Shoot your sticky grenades at the walls and ceilings where the enemy won't notice them. A highly visible sticky grenade isn't going to net any kills.

• Use your grenades to get up to higher vantage points just like the Soldier's rocket-jump. The grenade launcher is an extremely effective weapon when attacking from above.

Heavy Weapons Guy

The tanks of TF2. The Heavy Weapons Guy has tons of ammo and tons of health, but his mobility is terrible. Almost incapable of acting independently due to his vulnerability, the HW Guy relies on support classes to keep him alive in battle.

• Spin up your weapon when you turn a blind corner. If there's the potential for an enemy to be there, you don't want to be caught with your pants down. The 1-2 seconds it takes for your gun to spin up can be the difference between life and death.

• Team up with a Medic. His ability to keep you alive and your ability to deal out punishment make a great combo. Remember that as the slowest moving class, it's a huge penalty for you to die and have to walk all the way back to the front lines.

• Lead the charge. You're the biggest and most intimidating class on the team, so enemies will focus on you while your teammates take care of business.

Engineer

Engineers either make your life really easy or they make it really hard. Though Engineers might seem like a little bit of an extra, unnecessary class at first, their ability to create solid defenses and time-saving teleporters make them invaluable to the cause. If you're missing out on a good engineer, your team's in for a world of hurt.

• Build teleporters. On a linear progression map like Dustbowl, teleporters that spare your teammates a 20 second jog from the spawn point can turn the tide of the battle. Try to place them in hidden alcoves or side rooms, as you don't want your teammates teleporting into the middle of a firefight and don't want the teleporter easily destroyed by the enemy.

• Defend your turrets. You spend a lot of effort building them, so why abandon them? An undefended turret will die quickly, regardless of its location. Be on the lookout for Spies with their Sapper that can take out turrets in a hurry.

• Don't build turrets when you're on offense. This sounds like common sense, not to turtle when you're the attacking team, but I see plenty of Engineers attacking on Dustbowl by building useless turrets in areas that their team has already captured. That's time and ammo better spent on teleporters and dispensers to support the assault.